Abstract: This article discussed the fertilizer response in 3414 fertilizer experiments on peanut in Guangdong Province in recent years. The index system of soil available potassium abundance of Guangdong peanut was established by analyzing the relative yield. Results showed that, the equation for soil available potassium content was y=15.486lnx + 19.745 (r=0.701); the equation of the recommended potassium content was y=- 0.6357x+155.24 (r=-0.531). According to the mathematical model the sufficiency and deficiency range of the soil available potassium were divided into 5 levels: ＜20 mg/kg, 20-35 mg/kg, 35-70 mg/kg, 70-130 mg/kg and >130 mg/kg, and the proposed index of potassium application were 142.5 kg/hm², 135.0-142.5 kg/hm², 112.5-135.0 kg/hm², 75.0-112.5 kg/hm² and 75.0 kg/hm², respectively.